Locking mechanism



Aug. 18, 1964 P. RICHTER 3,145,039

LOCKING MECHANISM Filed May 24, 1962 2 Sheets-Sheet 1 F/GZ INVENTOR.

P IQIQAIE BY a 1W rm Aug. 18, 1964 p, E "3,145,039

LOCKING MECHANISM Filed May 24, 1962 2 Sheets-Sheet 2.

V F/aa Q j //2 3/ L INVENTOR PA/Z/P 63am" BY Am, V M W ATTOENEVJ United States Patent 3,145,839 LGCKING MECHANISM Philip Richter, Bethlehem, Pa, assignor to Fuller Company, Catasaunua, Pa, a corporation of Delaware Filed May 24, 1962, Ser. No. 197,408 4 Claims. (Cl. 292--2S6.5)

This invention relates to the art of locking mechanisms and more particularly to latches useful for marine application such as on hatch covers.

As conducive to an understanding of the invention, it is noted that where a hatch cover or panel on a hatchway is retained in position by a conventional locking mechanism of the type including a ring pivotally mounted on the deck of the ship and adapted to engage a hook fixed with respect to the hatch cover, as the locking ring and the hook must be spaced a predetermined distance apart for effective locking action and watertight security, precise tolerances are required in their positioning on the deck and the hatch cover.

Furthermore, as the ring may stretch slightly with repeated use, even with such initial precise tolerances, watertight security may not be maintained and the ring may have to be replaced with resultant cost and inconvenience.

It is accordingly among the objects of the invention to provide a latch of the type having a pivoted locking member adapted to be engaged by a pivotally mounted ring to eifect the locking action, and though of universal application, it is especially suited for marine use to retain a hatch cover in secured position with respect to a hatch opening, which latch has but few relatively inexpensive parts which may readily be fabricated and installed at relatively low cost and without the need for precise tolerances in the positioning of the elements thereof and which may readily be adjusted to take up any stretching of the ring with long use and which may readily be locked or unlocked without the need for loosening of nuts and with but simple manipulations that may readily be performed with a minimum of effort.

According to the invention, complementary locking members are provided including a pivotally mounted locking hook and a pivotally mounted resilient ring, preferably of spring steel, designed to be moved into and out of engagement with said hook. The ring is mounted so that it may readily be moved toward and away from the hook for adjustment of the distance therebetween and means are provided to rotate said locking hook between locked and unlocked position.

In the accompanying drawings in which are shown one of various possible embodiments of the several features of the invention,

FIG. 1 is a side elevational view of the latch;

FIG. 1a is a view taken along line 1a-1a of FIG. 1 showing the adjustment shims;

FIG. 2 is a front elevational View of the latch taken along line 2-2 of FIG. 1;

FIG. 3 is a view similar to FIG. 1, but showing the latch in open position, and

FIG. 4 is a top plan view of the latch showing the latter in locked position.

Referring now to the drawings, the locking mechanism is shown as the retaining means for the cover 11 of the hatchway of a ship. The side wall or skirt plate 12 of the cover has a resilient sealing strip 13 secured to the portion of the side wall adjacent its lower edge 14 so that when the hatch cover is in the closed position shown in FIG. 1, the strip 13 will become compressed against a sealing rail 15 around the coaming 16 of the hatchway to provide a watertight seal.

The locking mechanism comprises a plate 18 welded as at 19 to the outer surface of the side wall 12 of the cover.

Secured to the plate 13 is a bracket 22 which desirably has a body portion 23 that is secured to said plate 18 as by welding at 25. The front wall 26 of the body portion 23 of the bracket 22 has a pair of spaced parallel cars 27 extending outwardly therefrom, between which extends a pivot pin 23 retained in position by a set screw 29 extending vertically downward through one of the ears 27 as is clearly shown in FIG. 1.

A locking member 31 is pivotally mounted between the parallel arms 27' as is clearly shown in FIGS. 1 and 2. To this end, the locking member has a transverse bore 32 through which the pivot pin 28 extends. The locking member 31 has a fiat top surface 33 with a transverse arcuate groove 34 adjacent the front edge 35 of said locking member, said arcuate groove 34 defining a hook to receive the upper run 36 of a locking ring 37 in the manner hereinafter to be described.

The locking ring 37 which desirably is oval shaped and of resilient material such as spring steel, is mounted in fixed position with respect to the deck of the ship by means of a retainer member 41. The retainer member desirably comprises a rectangular block of rigid material such as steel, which block has a substantially U-shaped recess 42 in its undersurface extending transversely thereacross and designed pivotally to accommodate the lower run 43 of the locking ring 37. The block 41 has four vertical bores 44 therethrough, two illustratively on each side of the recess 42, each of said bores 44 being designed to accommodate a bolt 45 which extends through a corresponding opening 46 in a supporting member 47 rigid with the deck of the ship, lock nuts 48 encompassing the ends of the bolts 45 that protrude beyond the supporting surface 47 as is clearly shown in FIGS. 1, 2 and 3.

interposed between the bottom surface of the block 41 and the top surface of the supporting member 47 are a plurality of pairs of shims 49. As shown in FIG. la, the shims 49 are illustratively rectangular plates, each having a pair of spaced grooves 51 extending inwardly from one edge thereof and complementary to the bolts 45.

Thus, with the nuts 48 loosened, shims may be placed between the block 41 and the supporting member 47 so that the bolts 45 are accommodated in the recesses 51 in associated pairs of shims 49 and depending upon the number of pairs of shims 49 inserted between the supporting surface 47 and the block 41, the vertical distance between the upper portion of the recess 42 in block 41 and the lower portion of the recess 34 in locking member 31 may be adjusted.

The block 41 has associated therewith and desirably formed integral therewith on each side thereof as shown in FIGS. 2 and 4, for example, an outwardly extending finger 53 designed to be engaged by corresponding fingers 54 rigid with and preferably formed integral with the lower run 43 of the locking ring 37 as is clearly shown in FIGS. 1 and 2. The fingers 54 on ring 37 are spaced apart sufliciently so as to straddle the block 41 and are intended, when engaging the fingers 53 on the block 41 to prevent the locking ring 37 from pivoting in a clockwise direction beyond a predetermined position for the purpose hereinafter to be described.

The locking member 31 adjacent the rear surface 58 thereof has a bore or recess 59 therein extending at right angles to pivot pin 28 and designed to receive the end of an operating lever 61 which serves to pivot the locking member 31.

As is clearly shown in FIGS. 1 and 2, the lever 61 has a U-shaped bracket 62 secured thereto near its free end, the legs 63 of the bracket being designed to straddle the locking member 31 when the end of the lever 61 is positioned in the recess 59 to prevent rotary movement of the lever 61 in order that maximum force may be applied to the locking member when the lever is moved in operation.

The locking member 31 is so designed that when it is in its full clockwise position, as shown in FIG. 1, the front edge 35 thereof will abut against the front wall 26 of the body portion of bracket 22 to limit the pivotal movement of the locking member. In this position, as is clearly shown in FIG. 1, a line extending from the center of the upper run 36 of the locking ring 37 retained in hook 34 to the center of the lower run 43 thereof will be displaced to the right of a line extending from the center of the pivot pin 28 to the center of the lower run 43 to retain the locking mechanism in latched position.

To assemble the locking mechanism above described, say, five pairs of shims 49, each of which illustratively is in thickness, are positioned between the block 41 and the supporting surface 47 and the nuts 43 are then tightened.

Referring to FIG. 3, with the lever 61 removed from the locking member 31, the locking ring 37 is pivoted from the position shown in FIG. 3, in a clockwise direction so that its upper run 36 is positioned in the recess or hook 34 of the locking member 31. Thereupon, the end of the lever is positioned in the opening 59 of the locking member 31 and the locking member is then pivoted in a clockwise direction until its front surface 35 abuts against the surface 26 of the body portion of the bracket 22.

After the elements are thus positioned with the locking ring 37 not under any stress, with the hatch-cover 11 in closed position with gasket 13 compressed by loading the cover with suitable weights and with the lower edges 14 of the side walls or skirt plates 12 of the covers in contact with the sealing bar 15, the bracket 22 and plate 18 are welded together and the plate 18 is welded to the side wall 12 of the hatch cover.

Thereupon, the locking member 31 is pivoted to unlocked position as shown in FIG. 3; the nuts 48 are loosened and one of the pairs of shims 49 is removed, illustratively leaving only four pairs of shims, and the nuts 48 then tightened, such tightening of the nuts thus moving the block downwardly by a distance equivalent to the thickness of the removed pair of shims, i.e., illustratively V in the illustrative embodiment shown.

In the operation of the locking member, referring to FIG. 3, with the hatch cover in closed position prior to latching, due to the resilience of the gaskets 13, the lower edges 14 of the cover members will be spaced from the sealing bars 15 by a relatively small distance.

Prior to inserting the end of the lever bar 61 into the locking member 31, the locking ring 37 is pivoted in a clockwise direction from the position shown in FIG. 3 so that the upper run 36 of the locking ring is seated in the recess or hook portion 34 of the locking member. Thereupon, the end of the lever bar 61 is inserted into opening 59 and the lever bar and the locking member 31 pivoted in a clockwise direction from the position shown in FIG. 3 to the position shown in FIG. 1.

As one of the shims 49 has been removed, as previously described, when the locking ring is in the position shown in FIG. 1 in locked position with the lower edge 14 of skirt plate 12 seated against sealing bar 15, the locking ring 37 will be elongated by approximately i.e., the thickness of the shim that had been removed.

Assuming that with the materials used, such elongation required a tensile force of approximately 3,000 pounds, thereupon a downward force of 3,000 pounds will be applied to the hatch cover for each latch employed. The downward force preferably is twice that needed to deform gasket 13 to bring the edge 14 of skirt plate 12 in contact with sealing bar 15. As the center of the upper run 36 of the locking ring 37 is displaced to the right of the center of the pivot pin 28, the locking member 31 will be urged by the tensed locking ring 37 in a clockwise direction limited by the abutment of the front surface 35 of the locking member 31 against the surface 26 of the body portion of the bracket 22. Consequently, the locking ring will be retained in latched position.

In such position the fingers 54 of the lower run 43 of the locking ring 37 will be slightly spaced from the fingers 53 carried by the block 41 so that no interference will be afforded to the movement of the locking ring 37 to latched position by such fingers 53.

The purpose of such coacting fingers 53, 54 is to prevent inadvertent pivoting of the locking ring 37 in a clockwise direction so that it rests against the sealing bar 15 when the hatch cover is opened, thereby preventing closure of the hatch cover. With the abutment of fingers 53, 54, the maximum clockwise movement of the locking ring is such that at all times the hatch cover will be able to be moved to closed position.

It is to be noted that when the hatch cover is removed and there is no compression imparted to the gaskets 13, they are designed to protrude approximately beyond the edge 14 of the associated cover thereby insuring that when the hatch cover is in closed position and the latch tightened, a dependable watertight seal will be imparted by the compressed gasket 13.

With the construction above described, in the event of slight stretching of the locking ring 37 after long use, any resultant looseness in the latching action may be taken up by merely loosening the nuts 48 and removing one or more pairs of shims 49. This action may readily be accomplished without need for opening of welds or any special tools except for a wrench to engage the nuts 48.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope of the claims, it is intended that all matter contained in the above description as shown in the accompanying drawings, shall be interpreted as illustrative and not in a limited sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A releasable locking mechanism for a hatch cover of the type having a depending skirt plate adapted to have its lower edge seated on a fixed supporting surface, said mechanism comprising a locking member pivotally mounted with respect to said skirt plate, said locking member having a hook, a locking ring, a pivotal mount for a portion of said locking ring, means securing said pivotal mount in fixed position with respect to said fixed supporting surface, a portion of said locking ring opposed to the pivotally mounted portion thereof being adapted to engage said hook, said locking member being movable between locked and unlocked position correspondingly to move the hook thereof, said locking ring being under tension when the hook is in locked position engaged by the locking ring, and removable spacer means interposed between said pivotal mount and said fixed supporting surface to vary the distance of the pivotal mount of said locking ring from the fixed supporting surface to which it is secured, thereby to vary the distance between the portion of said locking ring engaging said hook when the latter is in locked position and the opposed pivotally mounted portion of said locking ring.

2. The combination set forth in claim 1 in which means are provided to limit the pivotal movement of said locking ring.

3. The combination set forth in claim 1 in which said pivotal mount for said locking ring comprises a block having an arcuate recess in its undersurface, a bolt extending through said block on each side of said arcuate recess, said fixed supporting surface having openings through which said bolts extend, nuts secured to the protruding ends of the bolts, said locking ring being sub stantially oval-shaped having a pair of parallel runs, one of said runs engaging said hook and the other of said runs being positioned in said recess and said removable spacer means comprises a plurality of superimposed shims securely retained in position between said block and the top surface of said fixed supporting surface when said nuts are tightened, said shims being movable laterally clear of said block when said nuts are loosened.

4. The combination set forth in claim 3 in which each shim comprises a plate having a pair of spaced grooves extending inwardly from an edge thereof and complementary to said bolts.

References Cited in the file of this patent UNITED STATES PATENTS Robinson Nov. 17, 1885 Prinzler Nov. 6, 1917 Schakel Jan. 10, 1922 Ausmus May 22, 1956 Appleton et a1. June 21, 1960 

1. A RELEASABLE LOCKING MECHANISM FOR A HATCH COVER OF THE TYPE HAVING A DEPENDING SKIRT PLATE ADAPTED TO HAVE ITS LOWER EDGE SEATED ON A FIXED SUPPORTING SURFACE, SAID MECHANISM COMPRISING A LOCKING MEMBER PIVOTALLY MOUNTED WITH RESPECT TO SAID SKIRT PLATE, SAID LOCKING MEMBER HAVING A HOOK, A LOCKING RING, A PIVOTAL MOUNT FOR A PORTION OF SAID LOCKING RING, MEANS SECURING SAID PIVOTAL MOUNT IN FIXED POSITION WITH RESPECT TO SAID FIXED SUPPORTING SURFACE, A PORTION OF SAID LOCKING RING OPPOSED TO THE PIVOTALLY MOUNTED PORTION THEREOF BEING ADAPTED TO ENGAGE SAID HOOK, SAID LOCKING MEMBER BEING MOVABLE BETWEEN LOCKED AND UNLOCKED POSITION CORRESPONDINGLY TO MOVE THE HOOK THEREOF, SAID LOCKING RING BEING UNDER TENSION WHEN THE HOOK IS IN LOCKED POSITION ENGAGED BY THE LOCKING RING, AND REMOVABLE SPACER MEANS INTERPOSED BETWEEN SAID PIVOTAL MOUNT AND SAID FIXED SUPPORTING SURFACE TO VARY THE DISTANCE OF THE PIVOTAL MOUNT OF SAID LOCKING RING FROM THE FIXED SUPPORTING SURFACE TO WHICH IT IS SECURED, THEREBY TO VARY THE DISTANCE BETWEEN THE PORTION OF SAID LOCKING RING ENGAGING SAID HOOK WHEN THE LATTER IS IN LOCKED POSITION AND THE OPPOSED PIVOTALLY MOUNTED PORTION OF SAID LOCKING RING. 